This invention relates to handwriting analysis. More particularly, the invention relates to a device and method for analyzing a handwritten specimen such as a signature or the like.
Fraudulent handwritten documents and signatures cause large financial losses. Untrained observers are not able to reliably distinguish authentic specimens from forgeries even with the availability of an authentic reference specimen.
This is particularly the case with large financial institutions which rely on signature identification for such media of exchange as checks, traveler's checks and the like.
At the present time, bank tellers and other employees are confined to visual comparison of the relevant signature with a previously executed signature on a bank card or the like. Since tellers and other bank employees are not document experts, it can be expected that numerous mistakes will be made in signature comparisons. Where reliance is had upon confirmatory signatures, such as those appearing on driver's licenses, credit cards and the like, such corrobatory documents can be as readily forged as the signature on the check or other article which is subject to confirmation.
Variations in the applied pressures, or in some combination of the applied pressures, direction and timing of the movement of a stylus during an act of handwriting are unique to an individual. The measurement of these variations has been the basis of several systems for handwriting analysis or signature verification. U.S. Pat. Nos. 4,008,457, 3,956,734, 3,563,097, 3,906,444, 3,480,911, 4,040,010, 4,040,011, 4,040,012, 4,308,522, 4,131,880 and 4,111,052 all teach special apparatus whereby the variations may be converted into electrical signals for analysis. Each requires the writer to use the device to produce the handwriting specimen. None is capable of examining a document.
Many prior art devices utilize pressure-sensitive pads or styluses which entail the execution of the signature at the bank or other location where a check or other document is presented for negotiation. Unfortunately, the present-day pressures on bank facilities render the utilization of such devices impractical. Moreover, most check signatures are inscribed prior to presenting at the teller window and, consequently, they are not subject to verification by the prior art devices which utilize the pressure stylus or plate methods of verification.
The variations in applied pressure and direction of the stylus during handwriting produce corresponding variations in the density of application of ink to the document. The document thus incorporates the idiosyncratic features inherent in the act of handwriting.
The technology of optical character recognition wherein a document is optically scanned is exemplified in the barcode reader of U.S. Letters Pat. No. 4,369,361 and similar devices operating on human readable characteristics, producing a binary representation of a scanned document. This has been useful in deciphering handwritten text, but the binary nature of the data precludes analysis of many idiosyncratic features.
The technology of digital image processing wherein a document is optically scanned with transformation of the optical density information to digital form preserves density variations, but produces a monumental amount of data which requires considerable processing power.